1. Field of the Invention
The present invention relates to semiconductor packages, and more specifically to semiconductor packages having passive components.
2. Description of the Related Art
A semiconductor package typically includes a circuitized substrate with one or more active devices attached thereon; packages including only one device are known as Single Chip Modules (SCM), while packages including a plurality of devices are called Multi Chip Modules (MCM). The active device is typically a chip, a small piece of a wafer a commonly made of Silicon, Germanium or Gallium Arsenide.
As the speed of electronic packages increase, noise in the DC power and ground lines increasingly becomes a problem. To reduce this noise, passive components such as decoupling capacitors are often used to reduce power supply noise which occurs due to change in potential difference between the ground voltage and the power-supply voltage supplied to the active device. The decoupling capacitors are placed as close to the active device as practical to increase their effectiveness. Typically the decoupling capacitors are connected to power and ground as close as possible to the active device.
Normally, the passive components are surface-mountable devices (SMD's) used in the so-called surface-mounting technique in which the passive components are directly secured to a substrate via two end contacts thereof. However, mounting the passive components directly to the substrate, as in many prior art packages, creates several problems. First, the requirement for the passive components to be disposed at predetermined positions on the substrate restricts the flexibility of substrate routability. Moreover, the area of the substrate increases with an increase in the number of passive components mounted thereon, thereby making the package efficiency unacceptably low.
It could be understood that the semiconductor package of the present invention may include more than one passive component and the passive components may include capacitors, resistors and inductors arranged as filters to suppress power source noises and attain speed-up of the operation of the chip.